That's just a label that they use for those who challenge their distorted application of scripture. They are not to be questioned or corrected because they follow a pattern of 'pure' worship. I am no bible scholar, but everything that I know or think I know, came from their publications. Their own material can expose them and they just shrug it off.
One elder asked me how I was able to give good talks. He mentioned that I sounded like a CO (I think he meant that in a good way). I told him that I take what an elder has said, and then contradict it. He didn't challenge my comment because he knew what I meant. Elders were exploiting their 'I never do wrong' card and implementing all kind of unscriptural rules. The rest of the elders were just sitting on their hands.
One elder said that if you went out in service for 2 hours a month, then you only loved Jehovah for 2 hours that month. Where is that scriptural? I blasted his comment at the next watchtower study and called it tantimount to emotional blackmail. The rest of the congregation was applauding my comment but the elders were stewing. I told one of the elders that they were being used by Satan. Remember Jesus telling Peter, "Get behind me Satan"? That was the point I was making. The PO wanted to come after me and I went straight to him and asked him to prove me wrong. He backed down.
I have no desire to challenge doctrinal issues among bible readers. People who have read the bible from cover-to-cover are entitled to their beliefs. But people who ignore the most fundamental aspects of what it means to be a true Christian are contemptable to me. Lip-service to the scriptures is just that. Their cruelty and distortions demonstrate their lack of understanding. It's nice to pull out the 'imperfection' card. To me, their best intentions have distorted truth and they have a label such as 'apostate' to use whenever they want to continue their lack of understanding.